use std::fs;
use std::error::Error;
use std::env;

pub struct Config {
    pub query: String,
    pub file_path: String,
    pub ignore_case: bool, 
}

impl Config { 
    pub fn build(args: &[String]) -> Result<Config, &'static str> {
        if args.len() < 4 {
            return Err(" [not enough arguments] ");
        }

        let query = args[1].clone();
        let file_path = args[2].clone();
        // let ignore_case = env::var("IGNORE_CASE").is_ok();
        // let ev = env::var("IGNORE_CASE");
        // match ev {
        //     Ok(v) => println!("{v}"),
        //     Err(_) => println!("_"),
        // }

        // case read the file HowToDealWithEnvVarible.md to learn about the env-varible
        let chk = env::var("IGNORE_CASE").is_ok();
        let ignore_case = if chk {
            // println!("test-1");
            env::var("IGNORE_CASE").is_ok()
        } else { 
            // println!("test-2");
            match args[3].parse() {
                Ok(p) => p,
                Err(_) => false,
            }
        };

        Ok(Config { query: query, file_path: file_path, ignore_case:ignore_case })
    }

    // fn new(args: &[String]) -> Config {
    //     if args.len() < 3 {
    //         panic!("** not enough arguments");
    //     }
    //     let query = args[1].clone();
    //     let file_path = args[2].clone();
    //     Config { query, file_path }
    // }
}

// fn parse_config(args: &[String]) -> Config {
//     let query = args[1].clone();
//     let file_path = args[2].clone();
//     Config { query, file_path }
// }

pub fn run(config: Config) -> Result<(), Box<dyn Error>>{
    let contents = fs::read_to_string(config.file_path)?;
    //    .expect("Should have been able to read the file");

    // println!("With text:\n{contents}");
    // for line in search(&config.query, &contents) {
    //     println!("{line}");
    // }

    let tmp = config.ignore_case;

    eprintln!("{tmp}");
    let result = if config.ignore_case {
        search_case_insensitive(&config.query, &contents)
    } else {
        search_case_sensitive(&config.query, &contents)
    };

    for line in result {
        println!("{line}");
    }

    Ok(())
}

#[cfg(test)]
mod tests {
    use super::*;

    // #[test]
    // fn one_result() {
    //     let query = "duct";
    //     let contents = "\
    //     Rust:
    //     safe, fast, productive.
    //     Pick three.
    //     ";
    //     assert_eq!(vec!["safe, fast, productive."], search(query, contents));
    // }

    #[test]
    fn case_sensitive() {
        let query = "duct";
        let contents = "\
Rust:
safe, fast, productive.
Pick three.
Duct tape.
";
        assert_eq!(vec!["safe, fast, productive."], search_case_sensitive(query, contents));
    }

    #[test]
    fn case_insensitive() {
        let query = "rUst";
        let contents = "\
Rust:
safe, fast, productive.
Pick three.
Trust me.
";
        assert_eq!(vec!["Rust:", "Trust me."], search_case_insensitive(query, contents));
    }


}

pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
    // vec![]
    let mut results = Vec::new();

    for line in contents.lines() {
        if line.contains(query) {
            results.push(line);
        }
    }

    results
}

pub fn search_case_sensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
    // vec![]
    let mut results = Vec::new();

    for line in contents.lines() {
        if line.contains(query) {
            results.push(line);
        }
    }

    results
}

pub fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
    let query = query.to_lowercase();
    let mut results = Vec::new();

    for line in contents.lines() {
        if line.to_lowercase().contains(&query) {
            results.push(line);
        }
    }

    results
}
